1 /* ScummVM - Graphic Adventure Engine
2 *
3 * ScummVM is the legal property of its developers, whose names
4 * are too numerous to list here. Please refer to the COPYRIGHT
5 * file distributed with this source distribution.
6 *
7 * This program is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version 2
10 * of the License, or (at your option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License
18 * along with this program; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
20 *
21 */
22
23 #include "ultima/nuvie/core/nuvie_defs.h"
24 #include "ultima/nuvie/misc/u6_misc.h"
25 #include "ultima/nuvie/core/map.h"
26 #include "ultima/nuvie/pathfinder/dir_finder.h"
27
28 namespace Ultima {
29 namespace Nuvie {
30
31 /** STATIC FUNCTIONS **/
32
33 /* From a normalized direction xdir,ydir as base, get the normalized direction
34 * towards one of the seven nearby tiles to the left or right of base.
35 * For rotate: -n = left n tiles, n = right n tiles
36 */
get_adjacent_dir(sint8 & xdir,sint8 & ydir,sint8 rotate)37 void DirFinder::get_adjacent_dir(sint8 &xdir, sint8 &ydir, sint8 rotate) {
38 struct {
39 sint8 x, y;
40 } neighbors[8] = { { -1, -1}, { +0, -1}, { +1, -1},
41 { +1, +0},/*ACTOR*/ { +1, +1},
42 { +0, +1}, { -1, +1}, { -1, +0}
43 };
44
45 for (uint32 start = 0; start < 8; start++)
46 if (neighbors[start].x == xdir && neighbors[start].y == ydir) {
47 sint32 dest = start + rotate;
48 while (dest < 0 || dest > 7)
49 dest += (dest < 0) ? 8 : -8;
50 xdir = neighbors[dest].x;
51 ydir = neighbors[dest].y;
52 break;
53 }
54 }
55
get_nuvie_dir(sint16 xrel,sint16 yrel)56 uint8 DirFinder::get_nuvie_dir(sint16 xrel, sint16 yrel) {
57 uint8 direction = NUVIE_DIR_N; // default
58
59 if (xrel == 0 && yrel == 0) // nowhere
60 return (direction);
61 if (xrel == 0) // up or down
62 direction = (yrel < 0) ? NUVIE_DIR_N : NUVIE_DIR_S;
63 else if (yrel == 0) // left or right
64 direction = (xrel < 0) ? NUVIE_DIR_W : NUVIE_DIR_E;
65 else if (xrel < 0 && yrel < 0)
66 direction = NUVIE_DIR_NW;
67 else if (xrel > 0 && yrel < 0)
68 direction = NUVIE_DIR_NE;
69 else if (xrel < 0 && yrel > 0)
70 direction = NUVIE_DIR_SW;
71 else if (xrel > 0 && yrel > 0)
72 direction = NUVIE_DIR_SE;
73 return (direction);
74 }
75
get_nuvie_dir(uint16 sx,uint16 sy,uint16 tx,uint16 ty,uint8 z)76 uint8 DirFinder::get_nuvie_dir(uint16 sx, uint16 sy, uint16 tx, uint16 ty, uint8 z) {
77 return DirFinder::get_nuvie_dir(get_wrapped_rel_dir(tx, sx, z), get_wrapped_rel_dir(ty, sy, z));
78 }
79
80 // oxdir = original xdir, txdir = to xdir
get_turn_towards_dir(sint16 oxdir,sint16 oydir,sint8 txdir,sint8 tydir)81 sint8 DirFinder::get_turn_towards_dir(sint16 oxdir, sint16 oydir, sint8 txdir, sint8 tydir) {
82 oxdir = clamp(oxdir, -1, 1);
83 oydir = clamp(oydir, -1, 1);
84 txdir = clamp(txdir, -1, 1);
85 tydir = clamp(tydir, -1, 1);
86 struct {
87 sint8 x, y;
88 } dirs[8] = {{ -1, -1}, { +0, -1}, { +1, -1}, { +1, +0}, { +1, +1}, { +0, +1}, { -1, +1}, { -1, +0}};
89 uint8 t = 0, o = 0;
90 for (uint8 d = 0; d < 8; d++) {
91 if (dirs[d].x == oxdir && dirs[d].y == oydir)
92 o = d;
93 if (dirs[d].x == txdir && dirs[d].y == tydir)
94 t = d;
95 }
96 sint8 turn = t - o;
97 if (turn > 4)
98 turn = -(8 - turn);
99 return (clamp(turn, -1, 1));
100 }
101
102 // xdir,ydir = normal direction from->to (simple method)
get_normalized_dir(MapCoord from,MapCoord to,sint8 & xdir,sint8 & ydir)103 void DirFinder::get_normalized_dir(MapCoord from, MapCoord to, sint8 &xdir, sint8 &ydir) {
104 xdir = clamp(to.x - from.x, -1, 1);
105 ydir = clamp(to.y - from.y, -1, 1);
106
107 /* uint16 dx = from.xdistance(to), dy = from.ydistance(to);
108 if(dx > 0 && dy > 0)
109 {
110 if(dx > dy) xdir = 0;
111 else if(dx < dy) ydir = 0;
112 }*/
113 }
114
115 } // End of namespace Nuvie
116 } // End of namespace Ultima
117